Ignition timer for internal-combustion engines



Nov. 3 1925- SHEARER 1,559,995

IGNITION TIMER FOR INTERNAL COMBUSTION ENGINES Filed June .21, 1924 INVENTOR @7366 flea?- m' ATTORNEYS Fate-med Nov. 3, 1925,

PATENT OFFICE.

VANCE SHEAR-ER, OF NEW YORK, N. Y.

IGNITION TIMER FOR INTERNAL-COMBUSTION ENGINES.

Application filed June 21, 1924. Serial No. 721,392.

To all whom it may concern:

Be 1t known that I, VANCE, Snnannn, a CltlZBn'Of the United States, residing at the borough of Manhattan, in the city, county,

and Stateof New York, have invented an Improvement in Ignition Timers for Internal-Combustion Engines, of which the following is a specification.

*My invention relates to timers such as employed to control the ignition in multiple cylinder internal combustion engines, and is well adapted for use in the ignition system of the well known Ford type of automobile, although it has other and more general fields ofusefulness. V -Theobject of my invention is to do away with the brass segments or fixed contacts and raceway into which they are embedded, and also to dispense with the traveling con tact or brush, thereby greatly lengthening the life of the timer, preventing all liability of pitting, while increasing its efficiency, by the employment of means for making and breakingthe electric circuit at the desired intervals, hereinafter described, in which other features of novelty and utility will be observed.

In the accompanying drawing:

, Figure 1 is an inner end view of a timer constructed in accordance with my invention, the cam shaft being in section.

Fig. 2- is a sectional view taken on the .broken line 2-2 of Fig. 1.

Fig. 3 is a front view of the timer partly in section, and i i Fig. dis a side elevation of the same also partly in section showing a modification in the construction of the body.

Similar reference characters denote like parts throughout the several views.

Referring to the drawing, the body of the timer is substantially hollow, and externally of .a shape similar to the present standard Ford timer, provided with the usual arm 11 having an opening 12 .atits free end to receive the connection for adjustment to advance or retard the spark. J

This body maybe entirely of metal as shown in F igs'i l and or the rear portion may be "made of metal "and th'o-cap lfifor front portion maybe made of condensit'e' or tum insulating material asshown inFigs. and 4. either case the metallic portion has aflat front 14, with "a central opening "15, through which-thefrontendof th cam shaft 16 extends. This flat front l t is .per- I fectly smooth and even on its rear or inner surface, and is provided with a plurality of equally and predeterminedly spaced holes 17, surrounding its central opening for the purposes hereinafter described. 7

18 denotes a cam of insulating material provided with a centralopening into which is secured a bushing 19, provided with an annular flange 20 at its rear bearing against the rear surface of the cam, while the forward end of the bushing projects a predetermined distance beyondv the front surface of the cam, and keyed or otherwise securely fixed to the cam shaft 16, whereby the said cam revolves with the shaft.

The cam is of uniform diameter throughout its greater portion, but at a predetermined point in its periphery is notched or provided with a transverse recess 21, the edges of which are rounded giving a slight taper to its sides; this recess is of predetermined depth, and the periphery of the cam is a perfectly smooth surface.

This cam serves to make and break the electric circuit between the body 10 and the spark plugs of the engine, by the mechanism next described.

A plurality of metallic blocks 22 are provided, each having a terminal 23, projecting from the interior of the casing 10 through one of the holes 17 in the flat front 14, and insulated therefrom, as shown in Fig. 2.

These terminals are preferably rounded and screw threaded a predetermined distance at their free ends.

Between each of the blocks 22, and the-inner surface of the front plate 1& there is a metal strip 24.

This strip is L shape so that a portion of it extends along one side of the block. A. strip of insulating material 25 of like shape to the metallic strip 24 is placed between I said strips 24t'a'nd the blocks 22. Both strips are provided withan opening for thepassage of the termmals 23; the openings 1n the metallic strips being of size to avoid an DOSSlbllltY of contact w th such 7 term nals jbut astan additional precaution a washer of insulatingmaterial maybe placed. in

said opening surrounding eachterminal.

' ,Eachblock 22 is providedwitha central transverse bore 27 which areenlarged within the blocks to form receptacles for the spiral springs 28. These spiral springs surcesses. The shanks of the plungers 29 are of a diameter to allow them to slide through the smaller part of the bores in each block, that is the portions of such bores back of the recesses containing the spiral springs. To the extreme end of each plunger spindle. outside the blocks 22, I securely attach a metallic disk 31, in any suitable manner, preferably by further reducing these ends of the spindles and passing them through holes in the disks, and then upsetting the ends of the spindles upon the disks.

It will be seen that the expansion of the spiral springs 28 will draw these disks 31, into contact with the metal strips 24;, by pressure upon the heads of the. plungers, and that pressure upon the heads of the plungers outside the blocks will compress the springs and break such contact.

The plunger heads 30 contact with the periphery ofthe cam 18, and unless one of such heads is brought into alignment with the recess 21, in the cam, the diameter of the cam is such as to force the plunger heads into the recesses in the blocks 22 against the tension of the spiral springs 28, thereby pushin the contact disks 31 away from the blocks 22 and metal strips 24:, holding the electric circuit open, but during the revolution of the shaft 16, carrying the cam 18, the plungers will be brought successively into alignment with the recess 21, when the spiral springs will expand forcing the plunger head in that position into the recess in'the cam,

' and draw the contact disk 31, connected with that plunger into contact with the metal stri 24 connected with that block, thus closing the electric circuit between the body of the timer and the terminal of that block.

Upon the threaded ends of the terminals 23 extending beyond the front of the casing, are look nuts 32, which securely hold the blocks 22 in their proper position, and above these look nuts there are binding nuts 33, for clamping the ends of conductor wires. In sulating washers 34 are placed between the lock nuts 32 and the casing, where the easing is entirely of metal.

It will be apparent, that where the casing is made of two parts as shown in Figs. 3 and a, the lock nuts 32, will securely hold the front member or cap 13, to the metal portion of the'body, thecap being provided with holes registering with the holes in the front of the metal portion'through which the terminals 23 pass.

I claim as my invention:

1. An ignition timer, comprising a casing, a plurality of plungers within the same,

bearing upon the bottoms of the re blocks for su orting the plungers and provided with terminals extending through the front of the casing, lock nuts secured to said terminals exterior of the casing, a rotary shaft extending into the casing, and a cam of insulating material keyed to said shaft and coacting with the plungers to make and break the electric circuit.

2. An ignition timer, comprising a casing, a plurality of metallic blocks within the same in spaced circular relation to each other and provided with terminals extending through the front of the casing, lock nuts secured to said terminals, a plurality of plungers supported in recesses in said blocks, spiral springs surrounding said plungers within such recesses, a metallic disk secured to one end of each, plunger, a rotary shaft extending into the casing, and a cam of insulating material keyed to said shaft and coacting with said plungers to make and break the electric circuit.

3. An ignition timer, comprising a casing, a plurality of metallic blocks within the same in spaced circular relation to each other and provided with terminals 'extending through the front of the casing, lock nuts secured to said terminals, a plurality of plungers supported in recesses in said blocks, spiral springs surrounding said plungers within such recesses, a metallic disk secured to one end of each plunger, a rotary shaft extending into the casing, and a cam of insulating material keyed to said shaft and provided with a depression in its periphery, the heads of said plungers being pressed into said recesses in the blocks by said cam during the rotation of the shaft until said de pression in the cam comes into alignment with a plunger head. I

4. An ignition timer, comprising a casing, a plurality of metallic blocks within the same in spaced circular relation and provided with terminals extending through the front of the casing, lock nuts secured to said terminals, a metallic strip between each block and the front of the casing provided with an opening for the passage of the terminals, said metallic strips extending along one side of the blocks, a strip of insulating material between said metallic strips and the blocks, a plurality of plungers provided at one end with a head and having reduced shanks supported iii recesses in said blocks, spiral springs surrounding the shanks of said plungers within said recesses, a metallic .dlsk secured to the end of each plunger shank beyond said metallic strips through which said shanks extend, a rotary shaft extending into the casing and a cam of insulating material keyed to said shaft provided with a depression in its periphery and coacting with said spiral springs to intermittently move said metallic disks into and out. of

contact with said metallic strips.

5, An ignition timer comprising a metallic shaft extending through said body and into body provided with a cap of insulating masaid cap, and a cam of insulating material terial, a plurality of plungers within the keyed to said shaft coacting with the plunmetallic body blocks for supporting the gers to make and break the electric circuit.

5 plungers and provided with terminals eX- g d y me this 16th day Of J H11 1 24.

tending through holes in said body and cap, lock nuts secured to said terminals a rotary VANCE SHE ARER, 

